Polarizers are an important optical element widely used in displays, communication systems, and sensors. Conventional polarizers are capable of converting non-polarized light to linear polarized light with one particular polarization direction, with the linear polarization direction being spatially uniform.
However, in certain applications, spatially non-uniform polarizers are desired. For example, some applications involving photoalignment technology require micro-patterned polarizers with spatially varying linear polarization directions. Other applications may require patterned polarizers which can generate both linear polarization with spatially varying directions, as well as circular polarization, for example polarization sensors.
Conventional patterned polarizers include micro-patterned polarizer arrays based on wire grid polarizers, photoaligned azo-dye polarizers, and liquid crystal micro polarizer arrays for image sensing. However, wire grid polarizers require photolithography and are cost-prohibitive with respect to multi-domain patterns, photoaligned azo-dye polarizers have insufficient extinction ratios, and the thickness of liquid crystal micro polarizer arrays causes problems in image sensing applications. Other conventional patterned polarizers are similarly overly complex for practical manufacturing purposes or suffer from other drawbacks rendering them unsuitable for practical applications.